A wide variety of automated clinical analyzers are known in the art and widely used in hospitals, clinics, and research laboratories. A particularly popular example of such a device is the multi-channel type analyzer in which a series of different tests are performed simultaneously and in parallel with one another. The typical multi-channel analyzer generally utilizes liquid or solid reagents to react with a particular constituent present in a sample in conjunction with a photo-optical system to determine the rate of reaction, constituent concentration in the sample, and the like.
The usual method employed for performing these photometric procedures is to place the sample solution in a small cell, tube, or cuvette provided with transparent walls and interposing the sample solution between a light source and a photosensitive detecting element. In order to perform multiple tests simultaneously on each sample most contemporary multi-channel analyzers utilize a number of small sample aliquots taken from a larger sample volume originally supplied to the machine. These larger sample specimens are stored and manipulated in cells or tubes of varying size and configuration, the most common being round, oblong sample or test tubes while others include rectangular or square cells and alternative configurations. This form of individualized sample processing avoids the problem of cross-contamination previously associated with earlier flow-through type devices.
Although multi-channel automated analyzers have received wide acceptance, there are certain drawbacks associated with their use. For example, to provide precise and accurate handling of the sample tubes it is necessary to position and align the tubes within the apparatus accurately so that the various sample aliquots may be automatically and consistently removed as needed. Additionally, in order to correlate the multiple test results properly with the appropriate samples an accurate identification and tracking systems must be utilized. As a result, a variety of specialized sample cells and identification means have been developed in the art. Unfortunately, the majority are machine specific which limits the applicability of the particular analyzer to only those samples which are properly packaged in the appropriate sample tubes or modified with potentially clumsy adapters. Additionally, relatively highly trained personnel are required to operate these machines effectively, as simple mistakes can render entire sample runs useless.
In order to handle the transportation, alignment, and tracking needs of large sample batches effectively, most prior art multi-channel analyzers utilize sample tube racks or carrousels which are organized and loaded with sample tubes prior to positioning within the analyzer input areas. Though these racks provide a degree of convenience in connection with sample tube handling and bulk storage and identification, they make it virtually impossible to interrupt the analyzer apparatus once a sequence has been started and also impose a degree of restriction with respect to the handling of individual sample tubes.
Another significant disadvantage associated with these types of automated analyzing equipment is their inability to perform emergency "stat" tests due to their relatively long and complex setup times and the resultant inability to interrupt the order and flow of the organized samples. Similarly, though a relatively rare occurrence, if a sample tube should fracture or leak the entire sample run may be jeopardized if the machine cannot be interrupted without losing track of the samples.
An alternative approach to sample tube handling has been the development of individual sample tube carriers which may be stored in racks and loaded into conveyor lines. For example, U.S. Pat. No. 3,916,157, issued Oct. 28, 1975, illustrates a specimen carrier for test tubes that is provided with a slotted base that will engage with a geared conveyor track for transporting the carrier through an automated analyzer. Additionally, each carrier is provided with its own identification tag so that the sample carrier can be identified. An alternative sample container is disclosed in U.S. Pat. No. 3,350,946, issued Nov. 7, 1967. This system utilizes a vial with a vertical T-shaped flange that enables it to be inserted into a carousel. A machine readable tag is attached to the vial for tracking purposes. Similarly, U.S. Pat. No. 4,944,924, issued Jul. 31, 1990, also discloses a test tube holder that pivots along a belt-like conveyor.
Though effective at overcoming some of the earlier drawbacks associated with bulky carrousels and similar sample tube handling apparatus, these devices fail to address the need for an adaptable sample tube carrier that will readily self-adjust to handle a wide variety of sample tube sizes and configurations without jeopardizing machine performance. Moreover, there remains a need to provide a sample carrier system that will allow an operator to conveniently manipulate or store individual samples as well as bulk quantities of individual samples.
An additional need exists for a sample tube carrier that will readily interface with an automated analyzer system yet allow for sample input interruption and "stat" tests. A need also exists for a sample tube carrier that will protect a sample tube from damage yet allow a defective or broken tube to be removed without interrupting the process of an analyzer apparatus. Moreover, it would be of significant benefit to the medical field and related professions to provide a sample carrier which simplified the level of skill necessary to effectively operate an automated processing apparatus.
Accordingly, it is an object of the present invention to provide a sample tube carrier that can be releasably linked with identical carriers into stable rows and racks for initial sample handling and transport yet which will readily interface with automated conveyor loading systems in both individual and bulk formats for automatic processing.
It is an additional object of the present invention to provide a sample tube carrier that will self-adjust to releasably receive and retain sample tubes or cells of varying sizes and configurations.
It is yet an additional object of the present invention to provide a sample tube carrier that will automatically align the vertical centerline of a sample tube with that of the sample tube carrier so that sample aliquots can be drawn accurately and repeatably from the center of the sample tube.
It is a further object of the present invention to provide a sample tube carrier that will readily interface with modern automated analysis equipment yet will relieve the human operator from complex handling and record keeping functions.
It is an additional object of the present invention to provide a sample carrier that is robust, simple and inexpensive to manufacture and operate, and which provides enhanced operator safety.